Hi Kees,
The NHS3152 is an NFC transponder, it has no reader capability. Therefore no EMC filter is necessary on the LA/LB pins.
The internal chip capacitance at the antenna inputs is 50pF. The impedance of the antenna should be such that is resonates slightly above 13.56MHz. This can be achieved by careful matching of the antenna inductance or in case of a too low inductance by adding an external capacitor across the antenna (pF range).
Please look at the https://community.nxp.com/docs/DOC-341105 for a nice explanation of the antenna design process.
Passive programming of the firmware of the NHS3152 is not supported.
Regards,
Mario